Accumulating in the Tumor Cells
After administration to the patient by injection, the nanoparticles will circulate in the bloodstream until they reach the tumor. The nanoparticles will then leave the blood vessels through the pores in the vessel walls and accumulate between the tumor cells.
For tumors and metastases to grow, they require a supply of blood to provide them with oxygen and nutrients. The blood vessels that surround tumors exhibit an uncontrolled and unnaturally fast growth; thus becoming more permeable for particles than healthy vessels are. Furthermore, tumor tissue often has limited lymphatic drainage, which causes particles that end up in tumors to remain there for a longer time than they would have done in healthy tissue (retention). After administration to the patient by injection, the nanoparticles will circulate in the bloodstream until they reach the tumor. The nanoparticles will then leave the blood vessels through the pores in the vessel walls and accumulate between the tumor cells. In this manner, the particle concentration in the tumor tissue is built up over a few hours. Researchers at Spago Nanomedical have demonstrated this tumor build-up in an article in PLOS ONE, where SpagoPix nanoparticles accumulate in tumors in a mouse model of breast cancer. In addition to the selective accumulation of SpagoPix in cancer tumors (ref).
The EPR-effect has been validated in several different cancers including breast, colorectal and pancreas. It enables efficacy independent on molecular interaction.
Spago’s nanomedical platform is made up by an organophosphosilane core with excellent chelating properties. By chelating a therapeutic radioisotope (177Lu; Tumorad) or the paramagnetic ion manganese (Mn; SpagoPix), Spago Nanomedical addresses significant clinical needs for treatment of aggressive tumor-resistant and metastatic cancer, and high-precision and high-resolution imaging of solid tumors and metastases.
The nanoparticle core is protected by a proprietary PEG-based coating which reduces protein binding and renders the particles long circulation half-lives. The size of the particles will dictate biodistribution and can be fine-tuned and optimized based on the sough after properties for the target indications.